1. Field of the Invention
The present invention is generally concerned with trunking, especially for electrical apparatus, of the kind including a body with inwardly directed lips and a cover which can be attached to the body.
2. Description of the Prior Art
It is directed both to the case where the lips on the body are directly part therefore, being carried by its side flanges, the cover extending between the side flanges and of itself closing the entire body, and the case where one or both lips are carried by a partition internal to the body, whether this is a fixed partition or a removable partition as described in French patent FR-A-2 642 911, for example, the cover extending only from one side flange to one partition or between two partitions, of itself closing only part of the body.
For reasons of simplicity it is assumed hereinafter that the lips are in all cases part of the body, even if they are carried by an internal partition removable therefrom.
The present invention is more particularly concerned with the case where snap fastener means are provided by the cover and the body for attaching the cover to the body.
The lips on the body are shaped as channels, for example, and the cover has two beads on the back adapted to snap into the lips, i.e. into the channel formed thereby.
Although this has the advantage that the cover can be attached to the body simply by forcing it into place, given the nature of the snap fastening means employed, the same cannot be said for its removal, there being virtually no means on the cover itself for getting a grip on it once fitted to the body.
However, it may be necessary to remove the cover, for example to carry out maintenance on the electrical apparatus concerned or to modify the installation.
The operative must then insert the blade of a screwdriver into the inevitable gap between one longitudinal edge of the cover and the respective lip on the body, in order to apply an extraction force to the cover by levering against the body.
This complies with relevant standards which, for safety reasons, allow for the possible need to use a tool to remove the cover.
However, using a screwdriver inevitably damages the body and/or the cover, leaving traces on one or both, to the detriment of the overall appearance.
A general object of the present invention is an arrangement which can avoid this drawback which is particularly troublesome given that during the normal service life of trunking it can be necessary to remove the cover several times.